Voltage regulators have been implemented in conventional dedicated power management integrated circuits (PMICs). A conventional PMIC, which is separate from other integrated circuits on a circuit board, may have difficulty meeting the droop (transient) and power (efficiency) requirements of a modern multi-core application processor or communication processor, for example.
There has been a growing interest in integrated voltage regulators implemented as part of system-on-a-chip (SOC) integrated circuit devices. Integrated voltage regulators, however, may present several challenges in chip design and layout. For example, passive components such as inductors and capacitors in voltage regulators may pose a design challenge, because passive components such as inductors and capacitors, especially those with large inductance and capacitance values, may have large form factors requiring large surface areas in SOC die layouts.
Moreover, a voltage regulator, such as an integrated switching voltage regulator, may require a high-capacitance-density and low-loss capacitor as well as a high-inductance-density and low-loss inductor, both of which occupy a significant amount of area of an SOC die. In addition to the large amount of die area required, conventional fabrication processes for integrating an inductor and a capacitor as part of a voltage regulator on an SOC die may require complicated and expensive process steps, due to different structures and materials used for inductors and capacitors in conventional fabrication processes.